Moving coil miniature angular rate sensor

Abstract

A steering rate sensing device for rolling air frames includes a base member for attachment to the air frame, a magnetic member fixed to the base member, and a pick up coil pivotally mounted to the base in close proximity to the magnet such that movement of the coil relative to the magnet generates a signal proportional to the steering rate of the rotating body.

Having described our invention, we now claim: 
     
       1. A steering rate sensing device adapted for use on a rotating body comprising: a base member including pivot support means fixed thereto for attachment directly to a rotating body for rotation therewith about a rotary axis, said pivot support means defining a pivot axis extending at an angle to said rotary axis,   magnetic means fixed to said base member for rotation therewith, and   a pickoff coil pivotally mounted on said pivot support means on said base member for rotation therewith, and for movement about said pivot axis relative to said magnetic means by gyroscopic precession in response to change in orientation of said rotary axis during rotation thereof for generating a signal.   
     
     
       2. The steering rate sensing device of claim 1, wherein said magnetic means is a permanent magnet. 
     
     
       3. The steering rate sensor of claim 1, wherein said magnetic means is an electromagnet. 
     
     
       4. The steering rate sensor of claim 3, wherein said pivotal axis of said coil intersects said rotary axis at a right angle thereto. 
     
     
       5. The steering rate sensor of claim 1, wherein said pivot axis is transverse to said rotary axis. 
     
     
       6. The steering rate sensor of claim 5, wherein said coil encircles said magnetic means. 
     
     
       7. The steering rate sensor of claim 6, wherein said coil is circular in configuration. 
     
     
       8. The steering rate sensor of claim 6, wherein said coil is generally rectangular in configuration. 
     
     
       9. The steering rate sensor of claim 1, wherein the axis of said base coincides with the rotary axis of said rotating body. 
     
     
       10. The steering rate sensor of claim 1, including damping means for damping the pivotal movement of said coil. 
     
     
       11. The steering rate sensor of claim 10, wherein said damping means comprises conductive material carried by said coil for enhancing shorted turn/eddy current damping thereof. 
     
     
       12. The steering rate sensor of claim 1 mounted in a rolling air frame having a predetermined induced roll about its longitudinal axis, thereby defining said rotary axis, said base member being fixed to said air frame, said pickoff coil being mounted for pivotal movement about said pivot axis at an angle intersecting said air frame rotary axis at right angles thereto.   
     
     
       13. The steering rate sensor of claim 1, wherein said sensor is enclosed by a cover made of a low reluctance magnetic material for defining a shield for shielding said sensor from external magnetic fields, for shielding adjacent areas from the sensor magnets, and for maximizing flux density within the sensor. 
     
     
       14. A steering rate sensing device for a rotating body comprising: a base member including trunion support bearings defining a pivot axis mounted in a rolling air frame having a predetermined induced roll about its longitudinal axis, thereby defining a rotary axis, said base member being fixed to said air frame, for rotation therewith about said rotary axis, said pivot axis intersecting said air frame rotary axis at right angles thereto,   magnetic means fixed to said base member for rotation therewith, and   a pickoff coil comprising a conductive wire wound circumferentially about an annular spool pivotally mounted on said base on said trunion support bearings for rotation therewith, and for movement relative to said magnetic means by gyroscopic precession in response to change in orientation of said rotary axis during rotation thereof for generating a signal.   
     
     
       15. The steering rate sensor of claim 14, wherein said coil is balanced about said pivot axis and said rotary axis. 
     
     
       16. The steering rate sensor of claim 14, including electrical conducting means for conducting electrical current from said coil past said trunion support bearings, said conducting means comprising a pair of nonconductive spacers disposed on opposite sides of each of said bearings, a conductive spring clip engaging each spacer, a conductive lead from said coil connected to one of said clips, an external lead connected to the other of said leads, and a flex lead connected between said clips.   
     
     
       17. The steering rate sensor of claim 15, wherein said spacers are generally disc shaped in configuration and are mounted coaxially of said trunion bearings.